Internal resistance fluid clutch

ABSTRACT

A transmission in which the input and output shafts are coupled by a fluid drive which is pressurized by eccentrically driven pumps, the variable speed fluid coupling being effective until a particular rotational speed is reached, at which speed the drive is positively locked. Means is also provided for locking the driven selectively at any speed. The transmission can be shifted between forward and reverse positions, and the shift mechanism incorporates braking means to facilitate gear engagement, and locking means operable in a stopped position, the arrangement being particularly adaptable to automotive vehicles.

United States Patent Clark 1 June 20, 1972 s41 INTERNAL RESISTANCE FLUID2,798,580 7/1957 Lenz ..192/60 CLUTCH Primary Examiner-Benjamin W. Wyche[72] Inventor: Marion Clark, 546 West Pleasant, Tulare, AssistantExaWm,- Randa|| Heald Callf- 93274 Attorney-Carl R. Brown 2 i [22] FiledOct 8, 1970 ABSTRACT [21] Appl' 84804 A transmission in which the inputand output shafts are coupied by a fluid drive which is pressurized byeccentrically [52] U.S.Cl. ..l92/60, 74/792 driven pumps, the variablespeed fluid coupling being effec- [51] lnt.Cl F16d31/02 tive until aparticular rotational speed is reached, .at which [58] Field of Search192/60 R, 53 R Speed the drive is Positively locked- Means is alsoProvided for locking the driven selectively at any speed. Thetransmission 56] References Cited can be shifted between forward andreverse positions, and the shift mechanism incorporates braking means tofacilitate gear UNITED STATES PATENTS engagement, and locking meansoperable in a stopped position, the arrangement being particularlyadaptable to automo- 2,086,519 7/1937 Barnes ..192/60 tive vehicles.2,243,652 5/1941 Reed ..192/60 2,670,827 3/1954 Sanders ..'.192/604Clelns, 9Drawlngl lgures I86 I88 I98 34 21 L 234 23s z 66 E 7 136 22 l[58 28 2 l I 70 I 24 74 1 as 1 I2 EF I56 1 42 44 Q5 0 I50 I 122 I, I68I66 5 25 I w 1 w I 4 52 Q o '28 IIIIIIVIIJ'II k '04 I I I58 I62 24PATENTEllJuwzo 1372 SHEET 2 OF 3 INVENTOR. MARION A. CLARK ATTORNEYPATENTEnJuu 2 0 I972 SHEET 3 OF 3 INVENTOR. MAR ION A. CLARK ATTORNEYINTERNAL RESISTANCE FLUID cwrcrr BACKGROUND OF THE INVENTION Vehicletransmissions of the automatic or semi-automatic type are usuallycomplex mechanisms involving turbines for fluid drive coupling, multiplestage gears and speed responsive shifting means to control the gearratios. Such mechanisms are costly, since many precision parts are used,and servicing is difficult.

SUMMARY OF THE INVENTION The transmission described herein is a simplemechanism in which the input and output shafts are coupled by fluidpressure means actuated by eccennically driven pumps. At low speeds, thedrive coupling is proportional to the resistance of the fluid through ametered flow path and, at a predetermined rotational speed, a speedresponsive valve element shuts off the fluid flow and locks the drive inpositive engagement. An auxiliary control permits locking of the driveat any speed when power is required. Gears are provided for forward andreverse drive, the shift mechanism incorporated a brake to retard therotating mechanism and facilitate gear engagement, and a lock to holdthe output shaft secure in a stopped or parked position. Thetransmission is readily adaptable to automotive vehicles withconventional engines.

The primary object of this invention, therefore, is to provide a new andnovel transmission.

Another object of this invention is to provide a new and improvedtransmission having a pumped fluid drive coupling effective to apredetermined speed, at which the fluid coupling becomes locked inpositive drive.

Another object of this invention is to provide a new and improvedtransmission having a simple gear shift mechanism for forward andreverse selection.

A further object of this invention is to provide a new and irriprovedtransmission in which a locking mechanism is incorporated in the gearshift.

Other objects and many advantages of this invention will become moreapparent upon a reading of the following detailed description and anexamination of the drawings, wherein like reference numerals designatelike parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical axial sectionalview of the transmission.

FIG. 2 is a sectional view taken on line 2-2 of FIG. 1.

FIG. 3 is a sectional view taken on line 3-3 of FIG. 1.

FIG. 4 is an enlarged sectional view taken on line 4-4 of FIG. 3.

FIG. 5 is a sectional view taken on line 5-5 of FIG. 1.

FIG. 6 is a sectional view taken on line 66 of FIG. 1.

FIG. 7 is a view similar to FIG. 1, but showing the drive couplinglocked and the gears engaged in forward drive positron.

FIG. 8 is a partial top plan view of the transmission.

FIG. 9 is a sectional view taken on line 9-9 of FIG. 7, with associatedmechanism indicated in broken line.

DESCRIPTION OF THE PREFERRED EMBODIMENT The transmission is contained ina generally cylindrical housing 10 having a front annular flange 12,which is secured to the existing rear flange 14 of an engine flywheelhousing 16. At the rear end of housing 10 is an end plate 18 secured toa rear annular flange 20 on the housing, the end plate having an axialbearing hub 22 in which the output shaft 24 is journalled. Aconventional worm type take-ofl drive 25 for the speedometer isincorporated in the bearing hub 22. The existing flywheel 26, fixed toinput shaft 28, has a rearwardly extending cylindrical sleeve fixedthereto, the sleeve having internal splines 32. Sleeve 30 rotates in abearing seal 34 supported on a web plate 36, which is held betweenflanges 12 and 14 transmission housing. It should be noted that thevarious bearings and seals in the unit are shown in simple fonn and maybe of any suitable conventional type.

In the forward portion 38 of housing 10 is a drive disc 40 having acentral boss 42 with external splines 44, which engage with splines 32indriving connection. With reference to FIG. 2, there are only half asmany splines 32 as there are splines 44, so that axially extendingchannels 46 are left open between alternate pairs of splines 44. Axiallyspaced from drive disc 40 is a cam disc 48, having an annular flange 50which is peripherally secured to the drive disc. Fixed to flange 50 is aradially inwardly extending eccentric cam ring 52, having a forwardlyprojecting rail 53. Extending axially through the boss 42 and cam disc48 is a cylindrical valve block 54, rotatably held in bearings 56 and 58in the boss and cam disc, respectively. The rear end of valve block 54is further sup ported in a fixed bearing 60 on a baffle plate 62,secured to an internal flange 64 in the forward housing position 38.

Fixed to the rear of valve block 54 is a brake drum 66 having an annularchannel 68, and fixed to the rear face of the brake drum is a couplingshaft 70, extending axially through the central portion 72 of housing10. Coupling shaft 70 is hollow and is divided by a wall 74 into a frontchamber 76 and a rear chamber 78, the latter having internal splines 80.Valve block 54 has a plurality of equally spaced, axially extendingpassages 82, three being shown as an example. In the forward end of eachpasage 82 is an inlet valve 84, and in the rear end of each is an outletvalve 86, the outlet valves opening into the front chamber 76. A typicalinlet valve 84 is shown in FIG. 4, in which a valve body 88 with anoutlet port 90 is held in place by a threaded end cap 92, the end caphaving an inlet port 94 normally closed by a ball 96, which is held by aspring 98. The outlet valves 86 are similar but with the ball and springreversed to allow rearward fluid passage only. Coupling shaft 70 hasmetering ports opening outwardly from front chamber 76, so that oil canpass into the central housing portion 72. The oil path, indicated bydirectional arrows in FIG. 1, is from the interior of boss 42 at theforward end of the valve block 54, through the valves into front chamber76 and out through ports 100. The oil returns through openings 102 inbaflle plate 62 and is delivered to the interior of boss 42 throughchannels 46. To assist the return flow, the front face of drive disc 40carries vanes 104, which pull the oil radially inwardly.

Oil is forced through the valve block 54 by pumps 106 secured on thevalve block, each pump communicating by a port 108 to one passage 82.Each pump has a piston 110 with an outwardly extending stem 112, at theouter end of which are cam following inner rollers 114 riding inside camring 52, and an outer roller 116 riding on the outside of rail 53 as inFIG. 4. This provides a positive push-pull drive and a spring 117 biasesthe piston 110 outwardly to prevent chattering of the rollers. The pumpsare inclined from radial positions against the direction of relativerotation of the cam ring, as shown in FIG. 3, in order to bending loadson the pumps. Each outward stroke of piston 110 draws oil through inletvalve 84 and the inward stroke forces the oil through out let valve 86.

Slidably mounted on coupling shaft 70 is a sleeve valve 118 which, in aforward position, covers and seals ports 100, but is normally biasedrearwardly by a spring 120. The sleeve valve is actuated by a governormechanism, comprising flyweights 122 pivotally mounted on brackets 124extending rearwardly from brake drum 66. Sleeve valve 118 has spacedannular teeth 126 and each flyweight 122 has a gear segment 128 whichengages the annular teeth, so that outward motion of the flyweightspulls the sleeve valve forward. In the closed position the forward endof the sleeve valve closes against a seal ring 130 fitted around theforward end of coupling shaft 70,asin FIG. 7. An internalsealring 131inthe rear portion of the sleeve valve seals against the coupling shaftas the sleeve valves slides. To assist the governor action, the fly sh"are and separates the flywheel housing from the interior of the 75positioned radially outwardly from ports 100, so that the ejected oilstrikes the flyweights. For some purposes it may be desirable to closethe sleeve valve before the governor takes effect. This is accomplishedby means of a fork 132 having rollers 134 riding in an annular channel136 in the rear portion of sleeve valve 118. The fork 132 is pivotallymounted on a rocker shaft 138 extending across the housing and joumalledin bearings 140 and 142. One end of rocker shaft 138 projects from thehousing and has an arm 144 fixed thereon, with a push-pull rod 146extending from the arm for connection to a suitable hand or footcontrol.

in therear portion 148 of housing is a generally conventional planetarygear assembly for forward or reverse drive. The assembly includes a gearshafl' 150 having an externally splined forward end 152 which slides inthe splined rear chamber 78 of coupling shaft 70. The rear end of gearshaft 150 is supported by a stubshaft 154 axially slidable in output M,shaft 24. Fixed on gear shaft 150 is a sun gear 156 meshed with a set ofplanetary gears 158 mounted in a cage 160, the planetary gears riding ina ring gear 162 with internal splinelike teeth 164. The cage 160 has aforwardly extended barrel portion 166, with a central hub 168 whichslides over coupling shaft 70 for axially alignment. On the outside ofbarrel portion 166 is an external spline ring 170 which meshes with ringgear teeth 164 in a rearwardly displaced position for forward drive.When the cage is moved forwardly the spline ring 170 locks into aninternal spline ring 172 fixed in the housing 10, to provide a reversedrive coupling. In neutral, asshown in FIG. 1, the spline ring 170 isfree between ring gear 162 and spline ring 172.

Shifting is accomplished by means of a fork 174 having rollers 176 whichride in an annular channel 178 on the forward end barrel portion 166.The fork 174 is fixed to a slide bar 180 axially slidably mounted in thespline ring 172 and a forward bearing lug 182, the top of the bar havinga toothed rack 184. In the top of central housing portion 72 is a shiftblock 186 pivotally mounted on a transverse pin 188 to swing from frontto rear, the shift block having a lower gear segment 190 which mesheswith rack 184. The upper portion of shifl lock 186 has a clevis 192 inwhich the shift lever 194 is pivotally held by a hinge pin 196 to swingfrom side to side.

v The shift mechanism is enclosed by a cover 198 secured to a platformportion 199 on top of housing 10, the cover having a longitudinal slot200 in which the shift lever travels from front to rear. At the forwardend of slot 200 is a laterally ofiset notch 202 and at the rear is asimilarly offset notch 204, in which the shift lever is held in theforward and reverse positions, respectively. At the center of slot 200is a transverse slot 206, on the same side as the offset'of notches 202and 204 and extending down the side of cover 198, so that the shiftlever 194 can swing down to a substantially horizontal position, asshown in broken line in FIG. 6.

The brake drum 66 is used to retard the rotating components whileshifting between forward and reverse. Within cover 198 is a brake bar208 of arcuate configuration, pivotally mounted on platform portion 199by hinge pins 210 and 212 to swing laterally. Brake bar 208 is ofiset tothe side of shift lever 194 opposite to the slot 206, the shift leverhaving a recessed roller 214' which rides on the brake bar. The forwardhinge pin 210 extends into the housing and carries an arm 216, on whichis a brake shoe 218 shaped to ride in channel 68. A torsion spring 220biases the brake bar 208 toward the shift lever 194 and to thedisengaged position of the brake shoe. Slot 200 is offset from thecenter line so that the shift lever must be pushed slightly to one side,toward the driver, to ride in the slot. This swings the brake bar 208 tothe side and presses brake shoe 218 into channel 68 to retard the brakedrum 66. At either the forward or reverse positions, the shift lever isbiased into the respective notch 202 or 204 by the brake releasingspring 220.

To provide security when the vehicle is not in use, a lock isincorporated in the transmission. Immediately below the brake bar 208 isan arcuate lock bar 222 on which roller 214 also rides. Lock bar 222 isattached to a bellerank 224 hinged on cover 198, a rod 226 extendingfrom the bellerank into housing 10 and being connected to an arm 228fixed to a lock shaft 230. The lock shaft is journalled in spline ring172 and in a bearing lug 232 in the rear housing portion 148. On therear end of lock shaft 230 is a pawl 234 having a prong 236 whichengages in any one of the circumferentially spaced notches 238 in therim 240 on the rear of ring gear 162. The pawl 234 is held in theunlocked position, shown in full line in FIG. 9, by the shift lever 194bearing against lock bar 222. When the shift lever is folded in theneutral position, a torsion spring 242 urges the pawl into lockedposition, shown in broken line in FIG. 9, the bellerank linkage beingindicated for reference.

In operation, the input shaft 28 drives the cam disc 48 through thesplined connection, the rotation of the eccentric cam ring 52 actuatingpumps 106. The resistance of the oil in being pumped through the valveblock 54 and out through ports 100 causes the valve block and couplingshaft 70 to rotate. At low speeds the transmission is thus a fluiddrive, with the coupling increasing porportionally with rotationalspeed. As speed increases, the flyweights 122 swing out, assisted by theoil flow from ports 100, causing the sleeve valve 18 to be pulledforward and close off the ports. The size of ports 100 determines theeflective circulation rate of the oil and is set, together with theinterior of the flyweights, so that at a predetermined speed, such as avehicle speed of 20 miles an hour, the sleeve valve 118 is fully closedand the drive coupling is esentially solid. When speed is reduced, thespring 120 opens sleeve valve 118 and the transmission reverts to fluiddn've. lffull power is needed at low speed, as when towing anothervehicle, obtaining engine braking efiect downhill, or other suchinstances, the sleeve valve can be closed manually by actuating fork132.

When shifling or putting the transmission into gear, with the engineidling, the shifi lever 194 is pulled toward the operator and thenmovedalong slot 200 in the required direction. This forces brake bar 208 tothe side and applies brake shoe 218 to the brake drum 66, to retard therotating mechanism and allow the spline ring 170 to slide intoengagement with either the ring gear 162 or spline ring 172. When theshifi lever is released into either notch 202 or 204, urged by spring220,'the brake is released and drive action commences. in park position,the shift lever is placed in neutral and swung-down into slot 206, whichcauses locking pawl 234 to engage and lock the gears.

in the simple form shown the transmission has a single forward gearratio and a similar ratio reverse. It will be obvious, however, that thepower coupling mechanism is readily adaptable to well known geararrangements providing a selection of drive ratios.

Having described my invention, 1 now claim.

1. A transmission for connection to a power unit casing having a powerinput shaft and a flywheel therein, the transmis- 5 sion comprising:

a housing having a forward end with means for attachment to the powerunit casing, and a closed rear end having an output shaft rotatablymounted therein;

a coupling shaft connected at the rear end thereof to said output shaft;

drive means connected to the forward end of said coupling shaft andhaving means for securement to the flywheel;

said drive means including a valve block fixed to said coupling shaft;

an externally splined rotatable;

an internally splined sleeve fixed to said flywheel and in which saidboss is held, the splined connection having open portions defining oilconducting channels;

at least one pump mounted on said valve block to pump oil therethroughand having an actuating connection to the flywheel;

and metering means for restricting the flow of oil, thereby causing adriving resistance between the flywheel and coupling shaft.

boss in which said valve block is 2. A transmission for connection to apower unit casing having a power input shaft and a flywheel therein, thetransmission comprising:

a housing having a forward end with means for attachment to the powerunit casing, and a closed rear end having an output shaft rotatablymounted therein;

a coupling shafi connected at its rear end to said output shaft andhaving a hollow chamber in the forward portion thereof;

drive means connected to the forward end of said coupling shaft andhaving means for securement to the flywheel;

said drive means including a valve block fixed to said coupling shah;

at least one passage extending substantially axially through said valveblock, with an inlet valve at the forward end and an outlet valve at therear end of said passage opening into said chamber;

at least one pump mounted on said valve block with a port communicatingwith said passage between the valves, said pump having an actuatingconnection to the flywheel;

said coupling shaft having metering ports opening from said chamber intosaid housing, for restricting flow of oil therethrough and causingdriving resistance between the flywheel and coupling shaft; and oilreturn flow means connecting the interior of said housing to the forwardend of said valve block. 3. A transmission according to claim 2, andincluding a sleeve valve axially slidably mounted over said couplingshaft;

said sleeve valve being axially biased clear of said metering P andspeed responsive actuating means comprising flyweights mounted radiallyoutwardly from said coupling shaft and connected to said sleeve valve toclose the sleeve valve over the metering ports at a predeterminedrotational speed. 4. A transmission according to claim 3, wherein saidmetering ports are radially aligned with said flyweights to direct oilflow against the flyweights.

1. A transmission for connection to a power unit casing having a powerinput shaft and a flywheel therein, the transmission comprising: ahousing having a forward end with means for attachment to the power unitcasing, and a closed rear end having an output shaft rotatably mountedtherein; a coupling shaft connected at the rear end thereof to saidoutput shaft; drive means connected to the forward end of said couplingshaft and having means for securement to the flywheel; said drive meansincluding a valve block fixed to said coupling shaft; an externallysplined boss in which said valve block is rotatable; an internallysplined sleeve fixed to said flywheel and in which said boss is held,the splined connection having open portions defining oil conductingchannels; at least one pump mounted on said valve block to pump oiltherethrough and having an actuating connection to the flywheel; andmetering means for restricting the flow of oil, thereby causing adriving resistance between the flywheel and coupling shaft.
 2. Atransmission for connection to a power unit casing having a power inputshaft and a flywheel therein, the transmission comprising: a housinghaving a forward end with means for attachment to the power unit casing,and a closed rear end having an output shaft rotatably mounted therein;a coupling shaft connected at its rear end to said output shaft andhaving a hollow chamber in the forward portion thereof; drive meansconnected to the forward end of said coupling shaft and having means forsecurement to the flywheel; said drive means including a valve blockfixed to said coupling shaft; at least one passage extendingsubstantially axially through said valve block, with an inlet valve atthe forward end and an outlet valve at the rear end of said passageopening into said chamber; at least one pump mounted on said valve blockwith a port communicating with said passage between the valves, saidpump having an actuating connection to the flywheel; said coupling shafthaving metering ports opening from said chamber into said housing, forrestricting flow of oil therethrough and causing driving resistancebetween the flywheel and coupling shaft; and oil return flow meansconnecting the interior of said housing to the forward end of said valveblock.
 3. A transmission according to claim 2, and including a sleevevalve axially slidably mounted over said coupling shaft; said sleevevalve being axially biased clear of said metering ports; and speedresponsive actuating means comprising flyweights mounted radiallyoutwardly from said coupling shaft and connected to said sleeve valve toclose the sleeve valve over the metering ports at a predeterminedrotational speed.
 4. A transmission according to claim 3, wherein saidmetering ports are radially aligned with said flyweights to direct oilflow against the flyweights.